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Fiverr Pro
English
$
USD
I will build a custom CRM or web app with net and secure API
PathumJay
About this gig
Off-the-shelf CRMs too expensive, too complicated, or missing what your business actually needs? I build custom CRMs and backend web apps designed around your exact workflow, on a secure, scalable ASP.NET Core and SQL foundation.
I am a senior software engineer with 7+ years of experience building enterprise systems, microservices and APIs on Microsoft technologies and Azure.
What I can build:
- Custom CRM: contacts, leads, deals, pipeline stages, notes and tasks
- Admin dashboards and reports
- Secure REST APIs for your web or mobile apps
- Integrations with email, WhatsApp, payment gateways and other systems
- Role-based access so each user sees only what they should
Built properly from day one:
- Clean architecture that is easy to extend
- Authentication, validation and secure data handling
- API documentation (Swagger) and handover notes
- Deployment to Azure or your preferred hosting (Premium)
You own the full source code. Hosting and third-party service costs are billed to you and not included.
Message me before ordering with your current process and must-have features so I can recommend the right package.
Get to know PathumJay
PathumJay
- FromSri Lanka
- Member sinceDec 2020
- Avg. response time1 hour
- Last delivery4 years
Languages
English
Senior .NET software engineer with 7+ years of professional experience building scalable, production-grade systems.
Backend: C#, ASP.NET Core, microservices, REST APIs
Cloud & DevOps: Azure, Kubernetes, Docker, CI/CD
Data: SQL Server, MongoDB, Redis
AI: LLM integrations and agentic pipelines with Claude API, LangGraph, FastAPI, ChromaDB
Send me your request and I'll deliver it right.
My Portfolio
Other Software Development Services I Offer
FAQ
Why a custom CRM instead of HubSpot or Salesforce?
No per-user monthly fees, it fits your exact workflow, and you own the code and data. If a standard tool already fits your needs, I will tell you honestly before you order.
Which database do you use?
SQL Server by default, with Entity Framework Core. PostgreSQL or MySQL are available on request. Tell me if you already have a database and I will build on top of it.
Do I get the full source code?
Yes. You receive the complete source code in a Git repository you own, plus handover notes and API documentation so any developer can maintain and extend it.
Do you build the frontend too?
Standard and Premium include a clean, responsive web interface for your team. The Basic package is backend and API only, ideal if you already have a frontend or mobile app.
